Which of the following is a hemiacetal?

Which set of reagents would most likely bring about the following transformation?

What is the correct assignment of the names of the following functional groups?

What product will result from the reaction shown?

The product, of the following reaction sequence,  

An ylide is a molecule that can be described as a ________.

Bonus question Provide a stepwise synthesis for the following.        he answer should be entered as in the following example: (this is an example!) 1. NaNH2   2. CH3CH2Br   3. H2, Lindlar’s Cat.    4. BH3, THF   5. H2O2, NaOH                          (Keep three spaces between each step) All chemicals and reagents  structures should be correct and with the proper sequence. No partial credit.

Which of the following is the least reactive toward addition of a Grignard reagent ?

Which of the following substituents is an ortho, para director?

The compound shown below can form a hemiacetal by reacting with itself in an acidic solution.What is the structure of this hemiacetal?